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Kepler-1704b
Kepler-1704b is a super-Jupiter on a highly eccentric orbit around the star Kepler-1704. It has a mass of 4.51 . The planet's distance from its star varies from 0.16 to 3.9 AU. It is a failed hot Jupiter, been scattered from its birth orbit to orbit with periastron just above tidal circularization distance. Characteristics Kepler-1704b is much more massive than Jupiter, at 4.51 M''J.'' The high planetary mass makes Kepler-1704b a super-Jupiter. Kepler-1704b goes on a highly eccentric 2.7 year-long (988.88 days) orbit around its star as well as transiting. The extreme eccentricity yields a temperature difference of up to 700 K. Star The star, Kepler-1704, is a G2, 5745-kelvin star from Earth and the sun. It has a mass of , a radius of , and a luminosity of . The high radius for the star's mass hints that Kepler-1704 is not a main-sequence star. See also *Gas giant *List of planet types * Kepler-419b *HD 80606 b HD 80606 b (also Struve 1341 B b or HIP 45982 b) is an eccent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Giant
A gas giant is a giant planet composed mainly of hydrogen and helium. Gas giants are also called failed stars because they contain the same basic elements as a star. Jupiter and Saturn are the gas giants of the Solar System. The term "gas giant" was originally synonymous with "giant planet". However, in the 1990s, it became known that Uranus and Neptune are really a distinct class of giant planets, being composed mainly of heavier volatile substances (which are referred to as "ices"). For this reason, Uranus and Neptune are now often classified in the separate category of ice giants. Jupiter and Saturn consist mostly of hydrogen and helium, with heavier elements making up between 3 and 13 percent of their mass.The Interior of Jupiter, Guillot et al., in ''Jupiter: The Planet, Satellites and Magnetosphere'', Bagenal et al., editors, Cambridge University Press, 2004 They are thought to consist of an outer layer of compressed molecular hydrogen surrounding a layer of liquid metallic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Super-Jupiter
A super-Jupiter is a gas giant exoplanet that is more massive than the planet Jupiter. For example, companions at the planet–brown dwarf borderline have been called super-Jupiters, such as around the star Kappa Andromedae. By 2011 there were 180 known super-Jupiters, some hot, some cold. Even though they are more massive than Jupiter, they remain about the same size as Jupiter up to 80 Jupiter masses. This means that their surface gravity and density go up proportionally to their mass. The increased mass compresses the planet due to gravity, thus keeping it from being larger. In comparison, planets somewhat lighter than Jupiter can be larger, so-called "puffy planets" (gas giants with a large diameter but low density). An example of this may be the exoplanet HAT-P-1b with about half the mass of Jupiter but about 1.38 times larger diameter. CoRoT-3b, with a mass around 22 Jupiter masses, is predicted to have an average density of 26.4 g/cm3, greater than osmium (22.6 g/cm3), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eccentric Orbit
In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit (or capture orbit), and greater than 1 is a hyperbola. The term derives its name from the parameters of conic sections, as every Kepler orbit is a conic section. It is normally used for the isolated two-body problem, but extensions exist for objects following a rosette orbit through the Galaxy. Definition In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a non-negative number that defines its shape. The eccentricity may take the following values: * circular orbit: ''e'' = 0 * elliptic orbit: 0 < ''e'' < 1 * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Unit
The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once each year. The astronomical unit was originally conceived as the average of Earth's aphelion and perihelion; however, since 2012 it has been defined as exactly (see below for several conversions). The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec. History of symbol usage A variety of unit symbols and abbreviations have been in use for the astronomical unit. In a 1976 resolution, the International Astronomical Union (IAU) had used the symbol ''A'' to denote a length equal to the astronomical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Jupiter
Hot Jupiters (sometimes called hot Saturns) are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods (). The close proximity to their stars and high surface-atmosphere temperatures resulted in their informal name "hot Jupiters". Hot Jupiters are the easiest extrasolar planets to detect via the radial-velocity method, because the oscillations they induce in their parent stars' motion are relatively large and rapid compared to those of other known types of planets. One of the best-known hot Jupiters is . Discovered in 1995, it was the first extrasolar planet found orbiting a Sun-like star. has an orbital period of about 4 days. General characteristics Though there is diversity among hot Jupiters, they do share some common properties. * Their defining characteristics are their large masses and short orbital periods, spanning 0.36–11.8 Jupiter masses and 1.3–111 Earth days. The mass c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methods Of Detecting Exoplanets
Any planet is an extremely faint light source compared to its parent star. For example, a star like the Sun is about a billion times as bright as the reflected light from any of the planets orbiting it. In addition to the intrinsic difficulty of detecting such a faint light source, the light from the parent star causes a glare that washes it out. For those reasons, very few of the exoplanets reported have been observed directly, with even fewer being resolved from their host star. Instead, astronomers have generally had to resort to indirect methods to detect extrasolar planets. As of 2016, several different indirect methods have yielded success. Established detection methods The following methods have at least once proved successful for discovering a new planet or detecting an already discovered planet: Radial velocity A star with a planet will move in its own small orbit in response to the planet's gravity. This leads to variations in the speed with which the star move ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or dwarf stars. These are the most numerous true stars in the universe and include the Sun. After condensation and ignition of a star, it generates thermal energy in its dense core region through nuclear fusion of hydrogen into helium. During this stage of the star's lifetime, it is located on the main sequence at a position determined primarily by its mass but also based on its chemical composition and age. The cores of main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Planet Types
The following is a list of planet types by their mass, orbit, physical and chemical composition, or by another classification. The IAU defines that a ''planet'' in the Solar System must orbit around the Sun, has enough mass to assume hydrostatic equilibrium, and has " cleared its neighborhood". There is currently no accepted definition for exoplanets. Under the IAU definition, true or "major planets" can be distinguished from other planetary-mass objects (PMOs), such as dwarf planets and sub-brown dwarfs. Nonetheless, certain planet types have been applied to other planetary-mass objects; the Pluto–Charon system has been referred to as " double dwarf planets", for instance. By mass regime By orbital regime By composition Other types See also * * Minor planet * * Stellar classification * Substellar object * Sudarsky's gas giant classification Notes References External links Periodic Table of ExoplanetsaPlanetary Habitability Laboratory Universit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-419b
Kepler-419b (also known by its Kepler Object of Interest designation ''KOI-1474.01'') is a hot Jupiter exoplanet orbiting the star Kepler-419, the outermost of two such planets discovered by NASA's Kepler spacecraft. It is located about 3,400 light-years (1040 parsecs from Earth in the constellation Cygnus. Characteristics Mass, radius and temperature Kepler-419b is a hot Jupiter, an exoplanet that has a radius and mass near that of the planet Jupiter, but with an extremely high temperature. It has a temperature of .http://www.hpcf.upr.edu/~abel/phl/hec_plots/hec_orbit/hec_orbit_Kepler-419_b.png It has a mass of 2.5 and a radius of 0.96 . Host star The planet orbits an ( F-type) star named Kepler-419. The star has a mass of 1.39 and a radius 1.75 . It has a surface temperatures of 6430 K and is 2.8 billion years old. In comparison, the Sun is about 4.6 billion years old and has a surface temperature of 5778 K. The star's apparent magnitude, or how bright it appears from E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 80606 B
HD 80606 b (also Struve 1341 B b or HIP 45982 b) is an eccentric and hot Jupiter 190 light-years from the Sun in the constellation of Ursa Major. HD 80606 b was discovered orbiting the star HD 80606 in April 2001 by a team led by Michel Mayor and Didier Queloz. With a mass 4 times that of Jupiter, it is a gas giant. Because the planet transits the host star its radius can be determined using the transit method and was found to be slightly smaller than Jupiter's. Its density is slightly less than Earth's. It has an extremely eccentric orbit like a comet, with its orbit taking it very close to its star and then back out very far away from it every 111 days. Discovery The variable radial velocity of HD 80606 was first noticed in 1999 from observations with the 10-m Keck 1 telescope at the W. M. Keck Observatory in Hawaii by the G-Dwarf Planet Search, a survey of nearly 1000 nearby G dwarfs to identify extrasolar planet candidates. The star was then followed up by the Geneva Ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HR 5183 B
HR 5183 b is an exoplanet located 102.7 light years away in the constellation of Virgo orbiting the star HR 5183. It has a mass of . It has a highly eccentric (e≃0.87) orbit which takes it from within the orbit of Jupiter to beyond the orbit of Neptune, which classifies it as an eccentric Jupiter and it has been nicknamed the "whiplash planet". It was discovered in 2019 based on two decades of radial velocity observations. In 2021, astrometric observations revealed that HR 5183 b has a nearly edge-on orbital inclination, and thus its true mass is close to its minimum mass. See also * Eccentric Jupiter *HD 80606 b *HD 20782 b HD 20782 b is an extrasolar planet located approximately 117 light-years away in the constellation of Fornax, orbiting the star HD 20782. This planet orbits in the most eccentric orbit known (as of November 2012), with a semi-major axis of ... References External links Astronomers find bizarre planet 'unlike any other discovered so far' C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 20782 B
HD 20782 b is an extrasolar planet located approximately 117 light-years away in the constellation of Fornax, orbiting the star HD 20782. This planet orbits in the most eccentric orbit known (as of November 2012), with a semi-major axis of 1.36 AU, and eccentricity e=0.97+/-0.01. As a result, it also has one of the most extreme temperature swings. See also * HD 80606 b HD 80606 b (also Struve 1341 B b or HIP 45982 b) is an eccentric and hot Jupiter 190 light-years from the Sun in the constellation of Ursa Major. HD 80606 b was discovered orbiting the star HD 80606 in April 2001 by a team led by Michel Mayor an ... References External links * Fornax (constellation) Exoplanets discovered in 2006 Giant planets Exoplanets detected by radial velocity {{extrasolar-planet-stub de:HD 20782 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
